[L., neut. sing. of ūnic-us UNIQUE a. So in G. and Du.] A unique example, specimen, or thing.
1885. Daily Tel., 14 July, 5/3. Some picture, work of art, or old book, which is represented to him as being a unicum.
1892. Mrs. J. P. Morgan, trans. Rubinsteins Conv. on Music, 26. The symphony in G minor (this unicum of symphonic-lyric).